The invention relates to a method for using applications in a mobile station, a mobile station (also called a mobile radio communication unit), and a system for effecting payments.
There are prior art mobile phones in which the control card includes a subscriber identification unit, such as the SIM (Subscriber Identity Module) used in GSM (Global System for Mobile Communications) standard based systems. The SIM comprises a control unit CPU (Central Processing Unit), program memory ROM (Read Only Memory), data memory suited for long-term storage EEPROM (Electrically Erasable Programmable Read Only Memory) and operation memory suited for saving data during use RAM (Random Access Memory). For using the mobile phone, a PIN (Personal Identification Number) number saved on the SIM must be given, generally when the mobile phone is switched on. Other user-specific information, such as telephone numbers, messages, etc. can also be saved in the data memory of the SIM.
There are now also mobile phones which have a data connector for connecting an external data processing unit, such as a portable computer. Thus the mobile phone can be used as a means for data transfer between the portable computer and some other data processing equipment through a radio communication network. In this way it is possible to establish a connection e.g. to the user's bank for checking the balance and effecting payments. However, an arrangement of this kind is not very practical, because a separate cable is needed between the computer and the mobile phone. In addition, the computer must be available for establishing e.g. a bank connection.
Wireless systems, so called smart cards or payment cards, are also known, the said cards being mostly used in payment applications, such as making payments in buses and public telephones. Smart cards like this generally include a central processing unit, a program memory and a data memory. The internal operation of the card in use is controlled by the CPU in accordance with the program code stored in the program memory. The data memory is used for saving information relating to the intended use of the smart card, such as its value in money. For performing the payment transaction, the card also contains means for data transfer, such as a transmitter/receiver based on electromagnetic induction. A disadvantage of smart cards of this kind is, e.g., the fact that several different cards may be needed for different kinds of payment, and so the user must carry a large number of cards. In addition, when the amount of money loaded in the card has been consumed, one needs to buy a new card or load a new amount of money in the card at a sales outlet offering a loading service.
The Japanese patent application JP 4 083 447 presents a mobile phone to which it is possible to add more properties by means of a separate memory card. An application like this is preferably arranged for a certain use, such as for increasing the saving capacity or the telephone number memory. Applications like this are based on a method in which the central processing unit of the mobile phone reads the data saved in the applications (memory cards) and operates in a predetermined way required by the data. A disadvantage of this method is the fact that the functions needed for performing different operations of the applications must be programmed to the central processing unit CPU in advance, whereby the development of new applications also requires changes in the programs of the central processing unit.
The international patent application WO 91/12698 presents a mobile phone to which it is possible to add properties by means of a separate add-in card, such as a smart card. In this way it is possible to restrict the use of the phone by preventing foreign calls, long-distance calls or calls to service numbers, for example. The information about call restrictions is saved on an add-in card which the user has to install in the mobile phone when it is being used. Thus the main use of this method is to prevent the use of some properties of the mobile phone.